Backrest construction for chairs and the like



G. KOCH Noir. 29, 1966 BACKREST CONSTRUCTION FOR CHAIRS AND THE LIKE Filed 001;. 21, 1965 INVENTOR. 650/?65 K06 BY 77 United States Patent 3,288,529 BACKREST CONSTRUCTION FOR CHAIRS AND THE LIKE George Koch, Cohourg, Ontario, Canada, assignor to Steelcase, Inc., Grand Rapids, Mich., a corporation of Michi an g Filed Oct. 21, 1965, Ser. No. 499,559

3 Claims. (Cl. 297-460) This invention relates to chairs and to the backrest portion thereof, and more particularly to a new form of backrest construction having a number of new and des1rable features and attributes.

As is well known, most of the many different types of upholstered chairs have a backrest portion. These are usually padded on the inner side, against which the back of a person sitting in the chair is rested, and they are closed on the opposite or rear side by an outer panel which conceals the ends of the upholstering material and gives a finished appearance to the chair. Almost as long as chairs have been made, the outside panel has been secured to the padded backrest by a contlnuous peripheral row of upholsterers tacks, nails, or screws, whose heads are plainly visible from the outside. This situation has provided a source of irritation for a long time, s nce the protruding tack or screw heads are incongruous in most design approaches, and they may actually be unsightly in many specific designs. Further, securing the outer panel to the backrest in this manner is time consuming and tedious, since the panel and backrest must be carefully aligned and held in an aligned position while each tack or screw is secured, and this has contributed to unnecessarily large labor costs incurred in chair assembly. However, even with all its inherent limitations, the foregoing method of chair construction is still in extensive use, since no better construction has yet been provided.

Accordingly, it is a major object of the present invention to provide a new construction for securing the outer panel to the backrest portion of a chair which eliminates substantially all visible assembly components and provides a smooth and uninterrupted outward appearance.

A further important object of the invention is to provide a backres't'constmction for chairs of the foregoing character in which the outer panel is resiliently deformed when it is secured to the backrest portion, so that the spring force of the resiliently deformed panel aids in the retention of the panel upon the backrest.

A further object of the invention is to provide a backrest construction of the nature described which is readily and swiftly assembled without the'need for any special tools and without the need for any elaborate or particular care to be exercised in maintaining the alignment of the panel and backrest during assembly.

A still further object of the invention is to provide a backrest construction for chairs of the character noted above, which produces no disfiguration of the outer surface of either the backrest or the outer panel, and which may be quickly and easily disassembled when desired and subsequently reassembled without producing any outward appearance change and without involving any construction problems whatever.

The foregoing major objects of the invention and the advantages provided thereby, together with additional objects and advantages, will become increasingly apparent following a consideration of the ensuing specification and its appended claims, particularly when taken in conjunction with the accompanying drawings setting forth preferred embodiments thereof.

In the drawings:

FIG. 1 is a fragmentary enlarged sectional elevation of a first form of backrest and outer panel, taken through the plane I-I of FIG. 2, showing a first embodiment of the invention;

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FIG. 2 is a fragmentary overhead plan view of the backrest and panel seen in FIG. 1;

FIG. 3 is an overhead plan view similar to FIG. 2, showing a slightly modified form of backrest and panel construction;

FIG. 4 is a sectional elevation similar to FIG. 1 but taken through the vertical plane lVIV of FIG. 5 showing 'a different form of backrest and panel and a different embodiment of the invention used in connection therewith;

FIG. 5 is a fragmentary overhead plan view of the structure illustrated in FIG. 4; and

FIG. 6 is a fragmentary overhead plan view similar to FIGS. 2, 3 and 5, but showing an additional embodiment of the invention.

Briefly stated, the present invention provides a backrest construction for chairs and the like, comprising a backrest structure which is connectable to a chair assembly, an outer panel for covering the rear of the said backrest structure, an interengageable structure operatively associated with both the backrest and the panel for providing a two-point interconnection therebetween, with the said interengageable structure having an interlocking position in which the backrest and panel are drawn closely together and a relaxed position in which the backrest :and panel are separable, and means for maintaining the interengageable structure in its interlocking position to retain the panel in place against the backrest.

Referring now in more detail to the drawings, a typical backrest structure 10 and outer panel 12 are illustrated in FIG. 1. The backrest structure generally includes a rigid structural member 14 which is typically formed from 'wood or other suitable material, a cushion 16 of polyfoam or the like which is usually affixed to the member 14, and an upholstering cover 18 which may be leather, fabric, or the like. The panel 12 has a generally rigid inner structural member 20 which is frequently of sheet metal but which may also be of wood or the like, and an outer covering 22 which normally is of the same upholstering material as the backrest cover 18.

It is desired to join the backrest structure 10 and panel 12 in a secure manner, and previously this was accomplished by driving tacks or screws completely around the perimeter of the panel into the member 14 of the backrest. However, in accordance with the present invention, recesses 24 and 26 (FIGS. 1 and 2) are formed in and preferably through the structural member 14, and a pair of brackets 28 and 30 are secured to the inner surface of the panel 12. Each of the brackets has an olfset upper portion such as 32 which extends laterally and upwardly away from the panel 12, for seating within the recess 24 by extending slightly behind the member 14,

in the opening which is indicated. Further, each of the brackets 28 and 30 have a generally horizontally disposed flange portion 34, which is located at the bottom of the panel and slightly below its lower extremity.

It is to be pointed out that the backrest structure 1 0 is often contoured by having a longitudinally curved form (see FIGS. 2, 3 and 6), and that in accordance with the present invention the panel 12 is preferably also curved longitudinally in this event, but with a different radius of curvature than that of the backrest 10. More specifically, the panel 12 of FIGS. 1 and 2 should have a lesser degree of curvature than the backrest 10 (i.e., radius R211 greater than R217, and in this case the recesses 24 and 26 and the brackets 28 and 30 should be rather widely spaced from each other and positioned near the outer ends of the backrest and panel. However, the panel 12 shown in FIG. 3 may be given a greater degree of curvature than the backrest 10 (i.e., radius R3a less than R3b), and in this case the recesses and brackets should be more narrowly spaced, and placed toward the center of the curvature, i.e., toward the center of the backrest and panel, as illustrated.

A slightly different form of backrest 410 and panel 412 is illustrated in FIGS. '4 and 5. This construction is often used in the case of typing chairs for secretaries, stenographers, and the like, and is typified by a downwardly depending resilient member 400 by which the assembled brackrest is mounted to the seat and legs of the chair. In this construction, a centrally-located recess 424 is formed in the wooden structural member 414 of the backrest 410, and the resilient member 400 is extending upwardly slightly to partially cover the recess at its lower extremities. An abbreviated fastening bracket is preferably used in this assembly. This consist of a shorter offset portion 432 secured to the inner panel member 420, which is similar in nature to the offset portion 32 of the bracket 28 seen in FIGS. 1, 2, and 3. A separate flange portion 434 is used, which extends dowlnwalrdly from the bottom of the: inner member 420 of the panel 412. As FIG. 5 illustrates, the backrest 41%] and panel 412 are also preferably longitudinally curved, with the panel having a lesser degree of curvature than the backrest (i.e., radius R5a greater than radius RSb), and with the offset bracket 432 and recess 424 being positioned centrally relative to the panel and backrest, respectively.

An additional embodiment of the concept underlying this invention is illustrated in FIG. 6, in which a curved backrest 610 and curved panel 612 are illustrated in the same manner as the structures of FIGS. 2, 3, and 5. In this embodiment, however, the projecting fastening bracket portions such as 32 and 432 seen previously are in the form of threaded bolting members 632 and 632 which extend through the panel 612. Further, the recesses 624 and 626 corresponding generally to recesses 24 and 424 seen previously are internally threaded so as to receive and engage the bolting members 632 and 632'. In the configuration shown in FIG. 6, it will be noted that the bolting members are recesses are relatively narrowly spaced, and that like the embodiment of FIG. 3, the curvature of the panel 612 is greater than that of the backrest 610 (Le, radius R6a is greater than radius R6b).

The assembly of the panels and backrest structures which have now been described is likely already apparent, and is extremely swiftly and easily accomplished. In the case of the structures of FIGS. 1, 2 and 3, the panel 12 is resiliently deformed or flexed so that its curvature closely approaches that of the backrest to which it is to be joined. The offset portions 32 of the panel brackets 28 and 30 are slidably inserted into the recesses 24 and 26, and the panel is then moved upward relative to the backrest. This interengages the vertically extending portion of the offsets 32 within the recesses and behind the wooden structural member 14, with the offset portions thus acting as hooking members.

Since the panel has been resiliently deformed, the spring force created thereby'continuously forces the panel backward away from the backrest, but since the offset portions of the brackets are engaged within the recesses, this spring force actually serves to clamp the periphery of 'the panel against the backrest, from which it cannot be removed without a deliberate downward sliding movement of the panel relative to the backrest. In the embodiments of the first three figures, such a downward movement maybe positively prevented by inserting a small screw or the like through a vertical aperture 35 formed in the horizontal lower flange 34 and into a vertical hole 36 formed in the bottom of the backrest (see FIG. 1) Such a screw will be essentially unobservable, since it is in the bottom of the backrest and completely out of the normal line of vision.

A very similar assembly is utilized in connection with the embodiment shown in FIGS. 4 and 5. Here the panel 412 is flexed slightly to increase its curvature to correspond to that of the backrest 410, and the offset or hooking member 432 is then inserted into the recess 424 and behind the upper end of the resilient mounting member 400'. The panel 412 is then moved downwardly relative to the backrest 410, and the same retention is provided as in the case of the previous embodiment. Also, in order to prevent any inadvertent upward movement of the panel 412 which would release it from the backrest 410, an appropriate screw or the like may be passed through an aperture 435 formed in the downwardly-depending flange 434 and into a threaded passage 436 formed in the resilient member 400, immediately beneath the backrest 410,

where the screw will be unobservable.

In the case of the embodiment shown in FIG. 6, it will be apparent that all that is required to assemble the panel 612 to the backrest 610 is to push the panel against the backrest at its center, so that the degree of curvature of the panel is reduced somewhat as the panel is resiliently flexed, and so that each of the bolting means 632 and 6,32 becomes aligned with its respective threaded recess 624 or 626. The bolting means are then merely turned to thread them into their respective recesses, and thereby interengage the structures to draw the panel tightly against the backrest structure. When this has been done, the spring force of the resiliently deformed panel will clamp the peripheral edges of the panel against the backrest. It will also tend to prevent the loosening of the bolting members by placing pressure against them, thereby maintaining the panel in place against the backrest.

From the foregoing, it will be clear that the projecting offset portions of the panel brackets and the projecting ends of the bolting means, together with the respective recesses in which these members become engaged, actually provide an interengageable structure which has an interlocking position in which the backrest and the panel are drawn closely together, and a relaxed position in which the backrest and panel are separable. This interengagement is maintained in its interlocked position by the screws which pass through the flange portions 34 or 434, or else by the threads which are formed upon the bolting members and within the recesses in the case of the embodiment of FIG. 6. Thus, regardless of the particular embodiment which is preferred, the panel will be firmly retained in place against the backrest.

The desirability of the advances which the construction of the' present invention makes over the methods and structures previously used will be immediately apparent to those who are skilled in furniture craftsmanship and upholstering. The resulting structure has a thoroughly finished appearance in which the rear panel becomes fully integrated into the design of the backrest construction, with no unsightly series of protruding tack or screw heads around the periphery of the panel. Of even greater importance to the manufacturer, however, is the fact that manufacture is greatly simplified and the ease and rapidity of assembly is increased by a multiple of many times. Further, if disassembly and subsequent reassembly become necessary, no scarring or defacing of either the panel or the backrest occurs, and the panel is as securely mounted to the backrest upon subsequent reassembly as it was when originally assembled.

It is quite possible that following a consideration of the foregoing specification, those skilled in the art will conceive of further embodiments of the concept which underlies the invention and of certain variations and modifications in the embodiments shown and described herein. Accordingly, all such embodiments, variations, and modifications as are clearly based upon thespirit of the invention and include its concepts are to be considered as within the scope of the claims appended herebelow, unless these claims by their language specifically state otherwise.

I claim:

1. A backrest construction for chairs. and the like, comprising in combination: a longitudinally curved backrest structure connectable to a chair assembly; a longitudinally curved outer panel for covering the rear of said backrest structure; said backrest and panel having different degrees of curvature and at least one of the same being resiliently deformable by flexing, to conform its curvature to that of the other; means defining at least one recess in one of said backrest and panel; at least hooking member operatively secured relative to the other of said backrest and panel; each such hooking member shaped and located so as to be insertable Within one such recess to engage therewith; When said backrest and panel are resiliently flexed into conformity with each other; said hooking member holding the resiliently conforming backrest and panel closely together when so engaged with said recess, and said resilient flexing simultaneously holding said hooking member and recess in firm engagement with each other; and means for maintaining said hooking member and recess in engagement, to retain said panel in place against said backrest.

2. The backrest construction of claim 1, wherein said panel has a greater degree of curvature than said backrest structure, and said hooking members and recess are located in the central area of the curvature.

3. The backrest construction of claim 1, wherein said panel has a lesser degree of curvature than said backrest structure and at least two of said hooking members and recesses are provided, each engageable pair thereof being Widely spaced from the other and located near the edges of the panel and backrest.

References ited by the Examiner FRANK B. SHERRY, Primary Examiner.

CASMIR A. NUNBERG, Examiner. 

1. A BACKREST CONSTRUCTION FOR CHAIRS AND THE LIKE COMPRISING IN COMBINATION: A LONGITUDINALLY CURVED BACKREST STRUCTURE CONNECTABLE TO A CHAIR ASSEMBLY; A LONGITUDINALLY CURVED OUTER PANEL FOR COVERING THE REAR OF SAID BACKREST STRUCTURE; SAID BACKREST AND PANEL HAVING DIFFERENT DEGREES OF CURVATURE AND AT LEAST ONE OF THE SAME BEING RESILIENTLY DEFORMABLE BY FLEXING, TO CONFORM ITS CURVATURE TO THAT OF THE OTHER; MEANS DEFINING AT LEAST ONE RECESS IN ONE OF SAID BACKREST AND PANEL; AT LEAST HOOKING MEMBER OPERATIVLEY SECURED RELATIVE TO THE OTHER OF SAID BACKREST AND PANEL; EACH SUCH HOOKING MEMBER SHAPED AND LOCATED SO AS TO BE INSERTABLE WITHIN ONE SUCH RECESS TO ENGAGE THEREWITH; WHEN SAID BACKREST AND PANEL ARE RESILIENTLY FLEXED INTO CONFORMITY WITH EACH OTHER; SAID HOOKING MEMBER HOLDING THE RESILIENTLY CONFORMING BACKREST AND PANEL CLOSELY TOGETHER WHEN SO ENGAGED WITH SAID RECESS, AND SAID RESILIENT FLEXING SIMULTANEOUSLY HOLDING SAID HOOKING MEMBER AND RECESS IN FIRM ENGAGEMENT WITH EACH OTHER; AND MEANS FOR MAINTAINING SAID HOOKING MEMBER AND RECESS IN ENGAGEMENT, TO RETAIN SAID PANEL IN PLACE AGAINST SAID BACKREST. 